Registering scripts with HttpModule

Question

I'm trying to add a javascript link to my Sharepoint page via a HttpModule, using the 'OnPreRequestHandlerExecute' event.

However nothing is happening and the script link is not added but i'm unsure why

public void Init(HttpApplication context)
{
    context.PreRequestHandlerExecute += OnPreRequestHandlerExecute;
}

void OnPreRequestHandlerExecute(object sender, EventArgs e)
{
    HttpContext currentContext = HttpContext.Current;
    Page page = currentContext.CurrentHandler as Page;

    if (page != null)
    {
        AddScript(page);
    }
}

void AddScript(Page page)
{

    var link = new ScriptLink
                          {
                              Defer = true,
                              Localizable = false,
                              Name = "_LAYOUTS/CompanyFolder/AcceptCookies.js"
                          };            

    page.Controls.Add(link);
}

Update 1

I also tried registering the script and this did not work either (with and without the ResolveClientUrl).

void AddScript(Page page)
{
    if (!page.ClientScript.IsClientScriptIncludeRegistered(scriptName))
    {
        string script = "<script type=\"text/javascript\" src=\"/_layouts/CompanyFolder/AcceptCookies.js\"></script>";
        page.ClientScript.RegisterClientScriptInclude(scriptName, page.ResolveClientUrl(script));
    }
}

Answer 1

You need to register the script. Something like :

if(!ClientScript.IsClientScriptIncludeRegistered("ScriptFile")) 
{      
    ClientScript.RegisterClientScriptInclude("ScriptFile", "/UserControls.js"); 
} 

Here is reference!

Answer 2

Why do you try to use HttpModule to add script on the page? In my practice I found out that the easiest way is to add script through delegate control. See this example. In this case you can easily activate/diactivate your script on the site pages by feature.